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Discussion Starter · #1 ·
Ok people, here's a good one: A HSH RG, measured on cable from the output jack - shows absolutely nothing when properly set to 20k to check impedance in all 5 positions. But the guitar plays fine (other than being too harsh for setting up to a lighter string gauge, from 0.010 to 0,009). I haven't touched the guitar for the last 2 years, I was playing the Strat so I almost thought I must have wired something out of phase.
Now - the multimeter is fine, the cable too - I have checked another guitar - all 5 positions show correct impedance.
Meter doesn't show the ''0'' value or something else, just the dot - like nothing is touched by the probes. All the pickups are good, Evolutions and True Velvet.
For the sake of the argument, it is wired like any other stock HSH RG, but with ''V-Treb'' treble bleed and the tone is DPDT so the humbuckers can be split in positions 1 and 5. Now, there's a lot of wire inside the cavity, it barely closes, so a lot could be happening inside when crammed. A cold solder joint most likely. It has to be I messed it up somewhere so double and triple-checking everything is a must, just thought I'd share the problem and ask for any ideas to maybe pinpoint the issue from the start.
 

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Discussion Starter · #5 ·
Everything works fine, that's the thing, I could just play it the way it is, but I think something is very wrong and about to get worse any moment so I have to deal with it.
 

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Well treble bleed is a HP filter...
It is but a normal treble circuit allows HF to bypass the series resistor of the volume potentiometer. The kind of HP filter that would cheat your resistance reading would be composed of a series capacitor and probably a resistor.
All this assumes - as I read your descriptipn - that the guitar generates output when you play it. A series HP filter might also explain the shrillness/brittleness you mention. Open it it and check/verify the wiring if you want to find out.
 

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Discussion Starter · #7 ·
Well thanks for your insight, it's actually something that crossed my mind too, that is the first thing I'm gonna check. The guitar works, but it does sound shrill...
Here is the link to what I'm using V-Treb Variable Treble Bleed Circuit
and the screenshot. I'm not really sure of the components it's not written anywhere, I see a capacitor, a resistor and another variable resistor, values unknown...It is wired using two long leads - then the whole circuit is stuck upside down (it has adhesive tape on the bottom) to the cavity cover. Due to pressure from all the wires inside (everything is pretty jammed in there) I suspect some solder joint there got bad. However, back to the meter, I think I should check everything.
Product Yellow Font Software Screenshot
 

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If that is installed as shown in the circuits you should still see some resistance between 0 and 15k (depending on pickup and volume potentiometer adjustment). You will have to check the wiring for bad solders.
The only other possibility is that if you try to measure resistance through a stereo jack (TRS) and one of your terminals is connected to the R (ring) terminal ...
 

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Discussion Starter · #9 · (Edited)
So far, I have no continuity between the 5-way switch and the volume pot, that's for damn sure, so that's one thing.
''you should still see some resistance between 0 and 15k (depending on pickup and volume potentiometer adjustment '' - not sure what you mean - I should see resistance measured on the guitar cable?
As for the treble bleed - the contacts to the pot lugs are fine...
EDIT:
The switch to pot ground connection was fine after all, all I did was reflow one of the pot ground blobs with pickup grounds - now everything is reading as it should. I'm curious will the sound still be chainsaw-like...
OK, so now the meter issue is fixed and the guitar sounds better BUT the volume pot has almost no taper.
Like almost nothing is happening until 2 or 3 where it gets louder with some kind of a gentle ticking sound - then at 6 or 7 it gets a bit quieter - abruptly goes up until 10. So not much taper between 3 and 10. I think I have read somewhere about this has to do with the treble bleed issue...
When measured from the cable on turning down, the pot tapers fine until 7, between 7 and 9 there is no reading at all then it reads fine again after that spot. Maybe the pot is fried, it is new but I had some problems with my soldering iron tip so I had to change it. So maybe I changed it AFTER it shot the pot. I'll try some contact cleaner but I doubt it will do some good.
 

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Discussion Starter · #11 · (Edited)
Well, the circuit is AC, so I guess impedance? I'm obviously not very technically savvy but the voltages become DC in the amp...what do you mean, exactly? By checking the pickup value changes on turning via the cable tip and sleeve I was measuring the AC impedance. The pot alone, before installation was reading 437kOhms. Now I regret not checking the taper then.
 

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... until 2 or 3 where it gets louder with some kind of a gentle ticking sound - then at 6 or 7 it gets a bit quieter - abruptly goes up until 10. So not much taper between 3 and 10. I think I have read somewhere about this has to do with the treble bleed issue...
<- here we are talking signal from the guitar pickups,

... between 7 and 9 there is no reading at all ... then it reads fine again after that spot.
<- and this is ohm reading.

Maybe the pot is fried, it is new but I had some problems with my soldering iron tip so I had to change it. So maybe I changed it AFTER it shot the pot. I'll try some contact cleaner but I doubt it will do some good.
<- Unfortunately it appears so. Reflowing of the potentiometer solder blobs are best done quickly with a solder iron with a big tip (high heat capacity) or a solder gun. Electronics solder irons takes too long to heat the metal of the potentiometer casing (IME).
 

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Discussion Starter · #14 · (Edited)
That's exactly what I did. And what I'm doing now is measuring another pot (Ernie Ball 500K) to make sure I made a dumbass of myself for not checking if it's audio taper or linear BEFORE I went out of the store with two of those - one shot (or close to shot) and behaving like an audio taper.
Yup...that's it, these EB's are audio tapers, what I need here is a DiMarzio EP1201 Custom taper, which is I think, somewhere in between linear and logarithmic. Just to try it out.
 
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